Simplify OldAutoLocator and AutoDateLocator.

anntzer · anntzer · commit 1f53c6bfd06b · 2020-03-24T12:47:38.000+01:00
In both classes the `refresh` method only sets the `_locator` attribute,
which is only later called in `__call__` -- but `__call__` also calls
`refresh` first.  So we can instead inline the contents of `refresh`
into `__call__`, get rid of the `refresh` implementation (inheriting
the do-nothing implementation of the base class) and get rid of the
`_locator` attribute, as this has no publically observable effect.
Likewise, `AutoDateLocator.set_axis` can go.
diff --git a/lib/matplotlib/dates.py b/lib/matplotlib/dates.py
@@ -1220,7 +1220,6 @@ def __init__(self, tz=None, minticks=5, maxticks=None,
             at 6 hour intervals.
         """
         DateLocator.__init__(self, tz)
-        self._locator = YearLocator(tz=tz)
         self._freq = YEARLY
         self._freqs = [YEARLY, MONTHLY, DAILY, HOURLY, MINUTELY,
                        SECONDLY, MICROSECONDLY]
@@ -1258,9 +1257,10 @@ def __init__(self, tz=None, minticks=5, maxticks=None,
                           range(0, 24), range(0, 60), range(0, 60), None]
 
     def __call__(self):
-        """Return the locations of the ticks."""
-        self.refresh()
-        return self._locator()
+        # docstring inherited
+        dmin, dmax = self.viewlim_to_dt()
+        locator = self.get_locator(dmin, dmax)
+        return locator()
 
     def tick_values(self, vmin, vmax):
         return self.get_locator(vmin, vmax).tick_values(vmin, vmax)
@@ -1279,15 +1279,6 @@ def nonsingular(self, vmin, vmax):
             vmax = vmax + DAYS_PER_YEAR * 2
         return vmin, vmax
 
-    def set_axis(self, axis):
-        DateLocator.set_axis(self, axis)
-        self._locator.set_axis(axis)
-
-    def refresh(self):
-        # docstring inherited
-        dmin, dmax = self.viewlim_to_dt()
-        self._locator = self.get_locator(dmin, dmax)
-
     def _get_unit(self):
         if self._freq in [MICROSECONDLY]:
             return 1. / MUSECONDS_PER_DAY
@@ -1298,8 +1289,7 @@ def _get_unit(self):
     def autoscale(self):
         """Try to choose the view limits intelligently."""
         dmin, dmax = self.datalim_to_dt()
-        self._locator = self.get_locator(dmin, dmax)
-        return self._locator.autoscale()
+        return self.get_locator(dmin, dmax).autoscale()
 
     def get_locator(self, dmin, dmax):
         """Pick the best locator based on a distance."""
diff --git a/lib/matplotlib/ticker.py b/lib/matplotlib/ticker.py
@@ -2816,33 +2816,25 @@ class OldAutoLocator(Locator):
     """
     On autoscale this class picks the best MultipleLocator to set the
     view limits and the tick locs.
-
     """
-    def __init__(self):
-        self._locator = LinearLocator()
 
     def __call__(self):
-        """Return the locations of the ticks."""
-        self.refresh()
-        return self.raise_if_exceeds(self._locator())
-
-    def tick_values(self, vmin, vmax):
-        raise NotImplementedError('Cannot get tick locations for a '
-                                  '%s type.' % type(self))
-
-    def refresh(self):
         # docstring inherited
         vmin, vmax = self.axis.get_view_interval()
         vmin, vmax = mtransforms.nonsingular(vmin, vmax, expander=0.05)
         d = abs(vmax - vmin)
-        self._locator = self.get_locator(d)
+        locator = self.get_locator(d)
+        return self.raise_if_exceeds(locator())
 
-    def view_limits(self, vmin, vmax):
-        """Try to choose the view limits intelligently."""
+    def tick_values(self, vmin, vmax):
+        raise NotImplementedError('Cannot get tick locations for a '
+                                  '%s type.' % type(self))
 
+    def view_limits(self, vmin, vmax):
+        # docstring inherited
         d = abs(vmax - vmin)
-        self._locator = self.get_locator(d)
-        return self._locator.view_limits(vmin, vmax)
+        locator = self.get_locator(d)
+        return locator.view_limits(vmin, vmax)
 
     def get_locator(self, d):
         """Pick the best locator based on a distance *d*."""
